diff getCQT.m @ 0:22b10c5b72e8

Initial import of complete code and test files

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/getCQT.m	Wed Mar 13 10:33:43 2013 +0000
@@ -0,0 +1,47 @@
+function intCQT = getCQT(Xcqt,fSlice,tSlice,iFlag)
+%outCQ = getCQT(Xcqt,fSlice,tSlice,iFlag) computes a rasterized representation of 
+%the amplitudes of the calculated CQT coefficients for the frequency bins definded in vector fSlice and the 
+%points in time (time frames) defined in vector tSlice using the interpolation method defined in iFlag. 
+%Valid values for iFlag are:
+%
+%'linear'  ... linear interpolation (default)
+%'spline'  ... spline interpolation
+%'nearest' ... nearest neighbor interpolation
+%'cubic'   ... piecewise cubic interpolation
+%
+%If the entire CQT representation should be rasterized, set fSlice and
+%tSlice to 'all'.
+%The input parameter Xcqt is the structure gained using cqt(...).
+%The output parameter 'intCQT' is the same size as Xcqt.spCQT but is no
+%longer sparse since the zeros between two coefficients are replaced by
+%the interpolated values. The coefficients stored in 'intCQT' are now
+%real-valued since only the absolute values of the coefficients are
+%interpolated. If a spectrogram-like (rasterized) version of the CQT
+%coefficients including phase information is required, use the function
+%cqtPerfectRast() (see documentation for further information)
+%
+%Christian Schörkhuber, Anssi Klapuri 2010-06
+
+
+if ischar(fSlice), fSlice = 1:(Xcqt.bins*Xcqt.octaveNr); end;
+if ischar(tSlice)
+    lastEnt = find(Xcqt.spCQT(1,:),1,'last');
+    tSlice = 1:lastEnt;
+end
+if nargin < 4, iFlag = 'linear'; end;
+
+intCQT = zeros(length(fSlice),length(tSlice));
+bins = Xcqt.bins;
+spCQT = Xcqt.spCQT;
+octaveNr = Xcqt.octaveNr;
+spCQT = spCQT.';
+
+for k=1:length(fSlice)
+   oct = octaveNr-floor((fSlice(k)-0.1)/bins);
+   stepVec = 1:2^(oct-1):size(spCQT,1);
+   Xbin = full(spCQT(stepVec,fSlice(k)));
+   intCQT(k,:) = interp1(stepVec,abs(Xbin),tSlice,iFlag);
+end
+
+
+